Image capture apparatus having illumination section, monitoring system including image capture apparatus, method of controlling image capture apparatus, and storage medium

ABSTRACT

An image capture apparatus capable of improving the quality of an image captured using illumination. A multi-eye image capture section has image capture sections that capture images in different image capture ranges partially overlapping with each other to generate a wide-angle image. A single-eye image capture section captures an image in part of the image capture ranges of the multi-eye image capture section and changes an image capture direction. When performing image capture using illumination, the exposure level of a first image capture section of the multi-eye image capture section, having an image capture range overlapping with the image capture range of the single-eye image capture section is controlled to be lower than the exposure level of a second image capture section having an image capture range not overlapping with the image capture range of the single-eye image capture section.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to an image capture apparatus having anillumination section, a monitoring system including the image captureapparatus, a method of controlling the image capture apparatus, and astorage medium, and more particularly to an image capture apparatushaving an illumination section, which is used e.g. for surveillanceduring the night, a monitoring system including the image captureapparatus, a method of controlling the image capture apparatus, and astorage medium.

Description of the Related Art

To acquire a clear subject image even under a low-illuminationenvironment, such as during nighttime, there has been proposed an imagecapture apparatus that illuminates a subject using an infrared LED lightsource (see e.g. Japanese Laid-Open Patent Publication (Kokai) No.2013-41282).

However, even in a case where a perfect diffuse light source is used forillumination, the illumination intensity at an illuminated flat surfaceis gradually reduced toward the periphery of the surface, compared withan illumination intensity at an area directly under the light source,according to the cosine fourth law, and hence it is difficult toilluminate a subject at a uniform illumination intensity. It is muchmore difficult to illuminate a subject at a uniform illuminationintensity, in a case where an LED light source having a lightdistribution with high directivity is used for illumination, asdisclosed in Japanese Laid-Open Patent Publication (Kokai) No.2013-41282.

In a case where it is impossible to illuminate a subject at a uniformillumination intensity as above, a subject within an image capture anglesuffers from an uneven luminance distribution, which degrades thequality of a captured image. Particularly, in a case where theunevenness in luminance distribution is large, overexposure orunderexposure is liable to occur in a captured image.

SUMMARY OF THE INVENTION

The present invention provides an image capture apparatus that iscapable of improving the quality of an image captured usingillumination, a monitoring system including the image capture apparatus,a method of controlling the image capture apparatus, and a storagemedium.

In a first aspect of the present invention, there is provided imagecapture apparatus comprising a multi-eye image capture section having aplurality of image capture sections that capture images in differentimage capture ranges partially overlapping with each other so as togenerate a wide-angle image, a single-eye image capture section that iscapable of capturing an image in part of the image capture ranges of themulti-eye image capture section and is capable of changing an imagecapture direction, an illumination section that has a peak ofillumination intensity within an image capture range of the single-eyeimage capture section, at least one memory that stores a set ofinstructions, and at least one processor that executes the instructions,the instructions, when executed, causing the image capture apparatus toperform operations comprising controlling, when performing image captureusing the illumination section, the exposure level of a first imagecapture section of the plurality of image capture sections of themulti-eye image capture section, which has an image capture rangeoverlapping with the image capture range of the single-eye image capturesection, such that the exposure level of the first image capture sectionbecomes lower than the exposure level of a second image capture sectionhaving an image capture range not overlapping with the image capturerange of the single-eye image capture section.

In a second aspect of the present invention, there is provided amonitoring system including an image capture apparatus and aninformation processing apparatus, wherein the image capture apparatuscomprises a multi-eye image capture section having a plurality of imagecapture sections that capture images in different image capture rangespartially overlapping with each other so as to generate a wide-angleimage, a single-eye image capture section that is capable of capturingan image in part of the image capture ranges of the multi-eye imagecapture section and is capable of changing an image capture direction,an illumination section that has a peak of illumination intensity withinan image capture range of the single-eye image capture section, at leastone memory that stores a set of instructions, and at least one processorthat executes the instructions, the instructions, when executed, causingthe image capture apparatus to perform operations comprisingcontrolling, when performing image capture using the illuminationsection, the exposure level of a first image capture section of theplurality of image capture sections of the multi-eye image capturesection, which has an image capture range overlapping with the imagecapture range of the single-eye image capture section, such that theexposure level of the first image capture section becomes lower than theexposure level of a second image capture section having an image capturerange not overlapping with the image capture range of the single-eyeimage capture section, and wherein the information processing apparatusdisplays the wide-angle image and an image captured by the single-eyeimage capture section, and transmits an instruction for controlling theimage capture apparatus to the image capture apparatus.

In a third aspect of the present invention, there is provided a methodof controlling an image capture apparatus including a multi-eye imagecapture section having a plurality of image capture sections thatcapture images in different image capture ranges partially overlappingwith each other so as to generate a wide-angle image, a single-eye imagecapture section that is capable of capturing an image in part of theimage capture ranges of the multi-eye image capture section and iscapable of changing an image capture direction, and an illuminationsection that has a peak of illumination intensity within an imagecapture range of the single-eye image capture section, the methodcomprising controlling, when performing image capture using theillumination section, the exposure level of a first image capturesection of the plurality of image capture sections of the multi-eyeimage capture section, which has an image capture range overlapping withthe image capture range of the single-eye image capture section, suchthat the exposure level of the first image capture section becomes lowerthan the exposure level of a second image capture section having animage capture range not overlapping with the image capture range of thesingle-eye image capture section.

In a fourth aspect of the present invention, there is provided anon-transitory computer-readable storage medium storing acomputer-executable program for executing a method of controlling animage capture apparatus including a multi-eye image capture sectionhaving a plurality of image capture sections that capture images indifferent image capture ranges partially overlapping with each other soas to generate a wide-angle image, a single-eye image capture sectionthat is capable of capturing an image in part of the image captureranges of the multi-eye image capture section and is capable of changingan image capture direction, and an illumination section that has a peakof illumination intensity within an image capture range of thesingle-eye image capture section, wherein the method comprisescontrolling, when performing image capture using the illuminationsection, the exposure level of a first image capture section of theplurality of image capture sections of the multi-eye image capturesection, which has an image capture range overlapping with the imagecapture range of the single-eye image capture section, such that theexposure level of the first image capture section becomes lower than theexposure level of a second image capture section having an image capturerange not overlapping with the image capture range of the single-eyeimage capture section.

According to the present invention, it is possible to improve thequality of an image captured using illumination.

Further features of the present invention will become apparent from thefollowing description of exemplary embodiments (with reference to theattached drawings).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic view of an image capture apparatus according to afirst embodiment, as viewed obliquely.

FIG. 1B is a view of the image capture apparatus shown in FIG. 1A, asviewed from above.

FIG. 1C is an internal function block diagram of the image captureapparatus shown in FIG. 1A.

FIGS. 2A to 2D are diagrams useful in explaining exposure level controlperformed by the image capture apparatus, for controlling the exposurelevels of a multi-eye image capture section, in a case where an imagecapture range of a single-eye image capture section, appearing FIGS. 1Ato 1C, overlaps only with an image capture range of one of image capturesections of the multi-eye image capture section, appearing in FIGS. 1Ato 1C.

FIGS. 3A to 3C are diagrams useful in explaining exposure level controlperformed by the image capture apparatus, for controlling the exposurelevels of the multi-eye image capture section, in a case where the imagecapture range of the single-eye image capture section overlaps withimage capture ranges of two image capture sections of the multi-eyeimage capture section and the image capture direction of one of the twoimage capture sections is closer to the image capture direction of thesingle-eye image capture section than that of the other is.

FIG. 4 is an internal function block diagram of an image captureapparatus according to a second embodiment.

FIGS. 5A to 5C are diagrams useful in explaining exposure level controlperformed by the image capture apparatus according to the secondembodiment, for controlling the exposure levels of a multi-eye imagecapture section in a case where the image capture range of a single-eyeimage capture section, appearing in FIG. 4, overlaps only with the imagecapture range of one of image capture sections of the multi-eye imagecapture section.

FIGS. 6A to 6C are diagrams useful in explaining exposure level controlperformed by the image capture apparatus, for controlling the exposurelevels of the multi-eye image capture section in a case where an imagecapture angle of the single-eye image capture section is wider than thatin the case shown in FIGS. 5A to 5C.

FIGS. 7A to 7C are diagrams useful in explaining exposure level controlperformed by an image capture apparatus according to a third embodiment,for controlling the exposure levels of a multi-eye image capture sectionin a case where an image capture range of a single-eye image capturesection overlaps only with an image capture range of one of imagecapture sections of a multi-eye image capture section.

FIG. 8 is a flowchart of a process performed by the image captureapparatus according to the third embodiment, for setting the exposurelevel of each image capture section of the multi-eye image capturesection.

FIG. 9 is a table showing a relationship between a position of a focuslens and a focal length, which is acquired by an image capture apparatusaccording to a fourth embodiment.

FIG. 10 is a table showing how the exposure level control of a multi-eyeimage capture section of an image capture apparatus according to a fifthembodiment is switched based on the image capture direction of asingle-eye image capture section of the image capture apparatus, in acase where the multi-eye image capture section and the single-eye imagecapture section are each equipped with a mechanism for inserting aninfrared cut filter therein or removing the same therefrom.

FIGS. 11A to 11C are tables each showing how the exposure level controlof the multi-eye image capture section is switched based on the imagecapture direction of the single-eye image capture section, in a casewhere an RGBIR sensor is further used in one or both of the multi-eyeimage capture section and the single-eye image capture sections.

DESCRIPTION OF THE EMBODIMENTS

The present invention will now be described in detail below withreference to the accompanying drawings showing embodiments thereof.

A description will be given of an image capture apparatus according to afirst embodiment with reference to FIGS. 1A to 1C. FIG. 1A is aschematic view of the image capture apparatus, denoted by referencenumeral 100, as viewed obliquely, FIG. 1B is a view of the image captureapparatus 100, as viewed from above, i.e. from a +Z axis based on a XYZcoordinate system indicated therein, and FIG. 1C is an internal functionblock diagram of the image capture apparatus 100.

As shown in FIGS. 1A to 1C, the image capture apparatus 100 includes amulti-eye image capture section 110, a synthesis processor 114, asingle-eye image capture section 120, a controller 130, and a transfersection 140.

The multi-eye image capture section 110 includes a plurality of imagecapture sections 111 a to 111 d that capture images in different imagecapture ranges, which partially overlap, so as to generate a wide-angleimage 101.

The single-eye image capture section 120 includes a single image capturesection 121 that captures an image in part of the whole image capturerange covered by the multi-eye image capture section 110 so as toacquire a detailed image 102.

The controller 130 controls the overall operation of the image captureapparatus 100, including the operations of the multi-eye image capturesection 110 and the single-eye image capture section 120.

The transfer section 140 transfers the wide-angle image 101 and thedetailed image 102 to an external client apparatus. More specifically,the transfer section 140 is connected to the external client apparatuse.g. via a wired or wireless network, and switches an image to betransferred to one of the wide-angle image 101 and the detailed image102 by a switch, not shown, within the transfer section 140. With this,the wide-angle image 101 and the detailed image 102 are sequentiallytransferred from the transfer section 140 to the external clientapparatus via the same network.

The external client apparatus transmits a command for controlling theimage capture apparatus 100 to the transfer section 140 via the network.After that, upon transfer of the command from the transfer section 140to the controller 130, the controller 130 performs processingcorresponding to the command in the image capture apparatus 100, andtransmits a result of the processing to the client apparatus as aresponse to the command. The client apparatus is an external apparatus,such as a PC, and the network is formed by a wired LAN, a wireless LAN,or the like. Further, power may be supplied to the image captureapparatus 100 via the network.

That is, in the present embodiment, a monitoring system using the imagecapture apparatus according to the present invention is comprised of theimage capture apparatus 100 and an external client apparatus(information processing apparatus) connected to the image captureapparatus 100 via a network.

Next, the multi-eye image capture section 110 which is a multi-lenswide-angle camera will be described.

The multi-eye image capture section 110 includes the plurality of imagecapture sections 111 a to 111 d, which are arranged such that the imagecapture ranges partially overlap, and generates the wide-angle image 101using the synthesis processor 114 that synthesizes a plurality of imagesacquired by the image capture sections 111 a to 111 d. Morespecifically, the wide-angle image 101 is generated by applying atechnique of so-called pattern matching in which a correlationcoefficient is determined while shifting an overlapping part of imagesacquired by adjacent ones (e.g. the image capture sections 111 a and 111b) of a plurality of image capture sections, to thereby determinepositional shift amounts between the plurality of images. Note thatalthough in the present embodiment, the wide-angle image 101 isgenerated by the synthesis processor 114, this is not limitative. Forexample, the transfer section 114 (output unit) may output imagesacquired by the image capture sections 111 a to 111 d to an externalclient apparatus, and the external client apparatus may generate thewide-angle image 101 based on the images acquired by the image capturesections 111 a to 111 d.

The plurality of image capture sections 111 a to 111 d include imageforming optical systems 112 a to 112 d and solid-state image capturedevices 113 a to 113 d, respectively. The image capture sections 111 ato 111 d acquire images by causing subject images to be formed on thesolid-state image capture devices 113 a to 113 d via the image formingoptical systems 112 a to 112 d, respectively

Driving and signal reading of each of the solid-state image capturedevices 113 a to 113 d are controlled by the controller 130. That is,the controller 130 controls the exposure level of each of the imagecapture sections 111 a to 111 d of the multi-eye image capture section110 by controlling a time period over which charges are accumulated inpixels of the solid-state image capture devices 113 a to 113 d. Detailsof this exposure level control will be described hereinafter. Note thatthe exposure level control may be performed by controlling exposureparameters, such as a digital gain, an aperture value, and the densityof an ND filter or the like, which are associated with components foradjusting the light amount and exposure, other than the solid-stateimage capture devices 113 a to 113 d.

Next, the single-eye image capture section 120 which is a single-lenscamera will be described.

The single-eye image capture section 120 includes the single imagecapture section 121 formed by an image forming optical system 122 and asolid-state image capture device 123, a drive mechanism 124 which canchange an image capture direction, and an illumination section 125.Similar to the multi-eye image capture section 110, driving and signalreading of the solid-state image capture device 123 are controlled bythe controller 130.

The drive mechanism 124 includes a motor and a gear, and rotates thesingle-eye image capture section 120 as a single unit about a specificrotational axis by controlling electric power for driving the motor.This rotation of the single-eye image capture section 120, performed bythe drive mechanism 124, is controlled by the controller 130. Note thatthe drive mechanism 124 may be configured to have a plurality of motors,whereby the single-eye image capture section 120 may be rotated about aplurality of rotational axes.

The illumination section 125 is an LED formed by a compoundsemiconductor material, such as InGaN and AlGaAs, or an organicsemiconductor, and performs illumination in an image capture angle ofthe single-eye image capture section 120. More specifically, theillumination section 125 has a peak of illumination intensity within animage capture range of the single-eye image capture section 120. Theillumination light irradiated from the illumination section 125 is setto a wavelength to which the solid-state image capture devices 113 a to113 d and 123 of the image capture sections 111 a to 111 d and 121 havesensitivity. For example, in a case where the solid-state image capturedevices 113 a to 113 d and 123 are each formed using a silicon-basedcomponent, the peak wavelength of the illumination light is onlyrequired to be set to a value which is not smaller than 300 nm and notlarger than 1100 nm.

When image capture is performed using the illumination section 125, theimage capture apparatus 100 controls the exposure levels of theplurality of image capture sections 111 a to 111 d of the multi-eyeimage capture section 110 based on an image capture direction of thesingle-eye image capture section 120. More specifically, the exposurelevel(s) of any of the plurality of image capture sections 111 a to 111d forming the multi-eye image capture section 110, which has an imagecapture range at least partially overlapping with the image capturerange of the single-eye image capture section 120, is/are controlled toa value or values lower than the exposure level(s) of image capturesections each having an image capture range not overlapping with theimage capture range of the single-eye image capture section 120. Forexample, in a case shown in FIG. 1B, the exposure levels of the ones 111b and 111 c of the plurality of image capture sections 111 a to 111 dforming the multi-eye image capture section 110 are controlled to valueslower than the exposure levels of the others 111 a and 111 d, by thisexposure level control.

With this configuration, when image capture is performed using theillumination section 125, it is possible to reduce luminance unevennessof the wide-angle image 101, caused by light distribution ofillumination.

The following description is given of the exposure level control for themulti-eye image capture section 110 in a case where the image capturerange of the single-eye image capture section 120 overlaps only with theimage capture range of one of the image capture sections of themulti-eye image capture section 110, and does not overlap with the imagecapture ranges of the other image capture sections, in comparison with aconventional example.

FIG. 2A shows a state of the image capture apparatus 100 in which theimage capture range of the single-eye image capture section 120 overlapsonly with the image capture range of the image capture section 111 a ofthe multi-eye image capture section 110. FIG. 2B shows illuminationintensity distribution by the illumination section 125 in the stateshown in FIG. 2A, and FIG. 2C shows exposure levels set to the imagecapture sections 111 a to 111 d, respectively, for exposure leveladjustment to the illumination intensity distribution shown in FIG. 2B.Here, the exposure level refers to a so-called EV (Exposure Value). Thatis, when the EV is increased by 1, the luminance of the image is madetwice as high as before. FIG. 2D shows a shading correction value set ina case where not only exposure level adjustment shown in FIG. 2C, butalso shading adjustment is performed within the image capture range ofthe image capture section 111 a so as to make flat the pixel signallevels of the image capture sections 111 a to 111 d. This shadingadjustment will be described hereinafter.

As mentioned hereinabove, the illumination section 125 has a peak of itsillumination intensity in a direction in which the single-eye imagecapture section 120 is oriented. Therefore, in the case of theillumination intensity distribution shown in FIG. 2B, assuming that allof the image capture sections 111 a to 111 d of the multi-eye imagecapture section 110 are equal in exposure level, only an image acquiredby the image capture section 111 a having the image capture rangeoverlapping with the image capture range of the single-eye image capturesection 120 becomes brighter than images acquired by the other imagecapture sections 111 b to 111 d. As a result, luminance unevenness iscaused in the wide-angle image 101 generated by synthesizing the imagescaptured by the image capture sections 111 a to 111 d.

In view of this, if the exposure level of the image capture section 111a is made lower than the exposure level of the image capture sections111 b to 111 d, a difference in brightness between the image acquired bythe image capture section 111 a and the images acquired by the imagecapture sections 111 b to 111 d is reduced. As a result, it is possibleto reduce luminance unevenness caused in the wide-angle image 101generated by synthesizing the images captured by the image capturesections 111 a to 111 d. Therefore, it is possible to improve thequality of the wide-angle image 101.

Note that the exposure levels of the image capture sections 111 a to 111d may be varied within the image capture angle of the single-eye imagecapture section 120. That is, in a case where the image capture range ofthe single-eye image capture section 120 overlaps with the image captureranges of a plurality of image capture sections of the multi-eye imagecapture section 110, the exposure level may be controlled to differentvalues between the image capture sections. More specifically, it ispreferable that as the image capture range of an image capture sectionis closer to the image capture direction of the single-eye image capturesection 120, the exposure level set to the image capture section iscontrolled to a lower value. Here, the term “image capture direction ofthe single-eye image capture section 120” refers to the direction of theoptical axis of the image forming optical system 122.

The following description is given, with reference to FIGS. 3A to 3C, ofthe exposure level control for the image capture apparatus 100, forcontrolling the exposure levels of the multi-eye image capture section110 in a case where the image capture range of the single-eye imagecapture section 120 overlaps with the image capture ranges of two of theimage capture sections of the multi-eye image capture section 110, andthe image capture range of one of the two image capture sections iscloser to the image capture direction of the single-eye image capturesection 120 than that of the other is.

FIG. 3A shows a state of the image capture apparatus 100 in which theimage capture range of the single-eye image capture section 120 overlapswith the image capture ranges of the image capture sections 111 a and111 b of the multi-eye image capture section 110, and the image capturerange of the image capture section 111 a is closer to the image capturedirection of the single-eye image capture section 120 than that of theimage capture section 111 b is. FIG. 3B shows illumination intensitydistribution by the illumination section 125, occurring in the stateshown in FIG. 3A, and FIG. 3C shows the exposure levels set to the imagecapture sections 111 a to 111 d in this state.

As is apparent from the illumination intensity distribution in FIG. 3B,when a comparison is made between illumination intensities associatedwith the image capture sections 111 a and 111 b, the illuminationintensity is higher in the image capture range of the image capturesection 111 a closer to the image capture direction of the single-eyeimage capture section 120 than in the image capture range of the imagecapture section 111 b. Therefore, it is possible to reduce luminanceunevenness of the wide-angle image 101 generated by synthesis by makingthe exposure level of the image capture section 111 a lower than that ofthe image capture section 111 b.

Further, in a case where spread of the illumination intensitydistribution by the illumination section 125 is wider than the imagecapture range of the single-eye image capture section 120, the exposurelevel control may be also performed for any of the image capturesections 111 a to 111 d of the multi-eye image capture section 110,outside the image capture range of the single-eye image capture section120. More specifically, this applies to the image capture section 111 cin FIG. 3B in which although the image capture range thereof does notoverlap with the image capture range of the single-eye image capturesection 120, the illumination intensity distribution by the illuminationsection 125 spreads to part of this image capture range. In this case,it is preferable to control the respective exposure levels of the imagecapture sections 111 c and 111 d to different values. More specifically,as shown in FIG. 3C, it is preferable to control the exposure level ofeach image capture section such that as the image capture range thereofis closer to the image capture direction of the single-eye image capturesection 120, the exposure level set to the image capture section is madelower.

On the other hand, there is a case where spread of the illuminationintensity distribution by the illumination section 125 is narrower thanthe image capture range of the single-eye image capture section 120. Inthis case, if there are a plurality of image capture sections of themulti-eye image capture section 110 of which respective image captureranges do not overlap with the image capture range of the single-eyeimage capture section 120 (the image capture sections 111 b to 111 d inFIG. 2B), it is preferable to set the exposure levels of these imagecapture sections to a common value, as shown in FIG. 2C.

The above description is given of the method of reducing luminanceunevenness of the wide-angle image 101 by adjusting the exposure levelof each of the plurality of image capture sections 111 a to 111 d of themulti-eye image capture section 110. In addition to this method, it ismore preferable to reduce luminance unevenness within the image captureranges (image capture angle) of the image capture sections 111 a to 111d. More specifically, it is only required to perform so-called shadingcorrection (adjustment) in which luminance unevenness is corrected inthe image capture range of each of the plurality of the image capturesections 111 a to 111 d of the multi-eye image capture section 110.

It is only required that coefficient of shading correction is determinedby measuring illumination intensity distribution by the illuminationsection 125 in advance. More specifically, it is possible to measure theillumination intensity distribution from images acquired by the imagecapture sections 111 a to 111 d when only the illumination section 125is lighted to a subject having uniform reflectance distribution.

In a case where the peak of the illumination intensity from theillumination section 125 coincides with the image capture direction ofthe single-eye image capture section 120, shading correction isperformed for any of the image capture sections 111 a to 111 d of themulti-eye image capture section 110, which has an image capture range atleast partially overlapping with the image capture range of thesingle-eye image capture section 120. More specifically, as shown inFIG. 2D, it is only required that shading correction is performed forthe image capture ranges of the image capture sections 111 a to 111 d ofthe multi-eye image capture section 110 such that the pixel signal levelis made higher as the image capture range is farther from the imagecapture direction of the single-eye image capture section 120.

FIG. 1C shows the case where only the single-eye image capture section120 includes the illumination section 125, but the multi-eye imagecapture section 110 does not include an illumination section. However,each of the image capture sections 111 a to 111 d of the multi-eye imagecapture section 110 may include an illumination section having a peak ofillumination intensity in its image capture range. In this case, an SNratio of the wide-angle image 101 in a low-illumination environment isimproved, and hence this configuration is further preferable.

Further, although FIGS. 1B and 1C show the case where the multi-eyeimage capture section 110 includes the four image capture sections 111 ato 111 d, the number of image capture sections included in the multi-eyeimage capture section 110 is not limited to four. For example, themulti-eye image capture section 110 may include two or three, or five ormore image capture sections. Further, the image capture ranges of themulti-eye image capture section 110 are not necessarily required to bethe ranges indicated by broken lines in FIG. 1B, but it may cover thewhole circumference of 360 degrees.

Further, in the present embodiment, the transfer section 140sequentially transfers images to the external client apparatus via thesame network by switching the image to be transferred to one of thewide-angle image 101 and the detailed image 102 by the switch, notshown, the transfer method is not limited to this. For example, theimage capture apparatus 100 may have a transfer section dedicated to thewide-angle image 101 and a transfer section dedicated to the detailedimage 102, and transfer the wide-angle image 101 and the detailed image102 to the external client apparatus via different networks,respectively. However, it is more preferable to distribute images viathe same network because it is easy to grasp correspondence between thewide-angle image 101 and the detailed image 102.

Further, the present embodiment shows an example in which the transfersection 140 transfers the wide-angle image 101 and the detailed image102 to the external client apparatus, and receives a command from theexternal client apparatus, and the controller 130 controls the operationof the image capture apparatus 100 according to the received command.However, this is not limitative. For example, the image captureapparatus 100 may include, in place of the transfer section 140, amemory for storing the wide-angle image 101 and the detailed image 102,a viewer for displaying the wide-angle image 101 and the detailed image102, stored in the memory, and an interface for receiving a command froma user. Alternatively, the image capture apparatus 100 shown in FIG. 1Cmay additionally include the above-mentioned memory, viewer, andinterface.

Although as the method of controlling the exposure levels of theplurality of image capture sections 111 a to 111 d of the multi-eyeimage capture section 110, the method of controlling the time period ofaccumulating charges in the pixels of the solid-state image capturedevices 113 a to 113 d is described by way of example, it is notnecessarily required to use this method.

For example, in a case where the image capture apparatus 100 includes again controller which controls signal amplification coefficients (gains)of the solid-state image capture devices 113 a to 113 d, the exposurelevel may be controlled by controlling the signal amplificationcoefficients. Note that in a case where the solid-state image capturedevices 113 a to 113 d each have an analog-to-digital conversionfunction therein, it is preferable that the gain controller controls thesignal amplification coefficients before analog-to-digital conversion(analog gains). Further, in a case where the image forming opticalsystems 112 a to 112 d of the plurality of image capture sections 111 ato 111 d each include an aperture control mechanism, the controller 130may control the exposure levels of the plurality of image capturesections 111 a to 111 d by controlling each aperture control mechanism.Further, in a case where the image forming optical systems 112 a to 112d each include a light absorbing filter and a mechanism for insertingand removing the light absorbing filter, the controller 130 may controlthe exposure level by controlling insertion and removal of the lightabsorbing filter using the mechanism. Alternatively, in a case where theimage forming optical systems 112 a to 112 d each include a variabletransmittance filter formed by a liquid crystal or the like as the lightabsorbing filter, the controller 130 may control the exposure level bycontrolling a voltage applied to the variable transmittance filter.Further, the plurality of exposure level control methods described abovemay be used in combination.

Further, in a case where the illumination intensity from theillumination section 125 is high, in addition to the control of chargeaccumulation time period, a frame rate of each of the image capturesections 111 a to 111 d of the multi-eye image capture section 110 maybe changed. The charge accumulation time period of the solid-state imagecapture devices 113 a to 113 d can be set to be longer as the frame rateis lower, and hence it is possible to increase the exposure level of theimage capture sections 111 a to 111 d. That is, the controller 130controls the image capture sections 111 a to 111 d of the multi-eyeimage capture section 110 such that the frame rate of one(s) whichhas/have the image capture range not overlapping with the image capturerange of the single-eye image capture section 120 is/are made lower thanthat of an image capture section having an image capture range at leastpartially overlapping with the image capture range of the single-eyeimage capture section 120. This makes it possible to further reduceluminance unevenness of the wide-angle image 101.

Next, a description will be given of a second embodiment. Componentelements of the present embodiment are denoted by reference numerals of200s. Further, the same component elements as those of the firstembodiment are denoted by reference numerals which are changed from 100sto 200s, and redundant description thereof is omitted.

An image capture apparatus 200 according to the second embodimentdiffers from the image capture apparatus 100 according to the firstembodiment in the construction of a single-eye image capture section220.

FIG. 4 is an internal function block diagram of the image captureapparatus 200 according to the second embodiment.

Referring to FIG. 4, the single-eye image capture section 220 of theimage capture apparatus 200 includes not only the same componentelements as those of the single-eye image capture section 120, but alsoa zoom control mechanism 226 that is capable of changing an imagecapture angle of an image capture section 221. The zoom controlmechanism 226 includes a motor and a gear, and the configuration may besuch that a zoom ratio is changed by moving one or some of the lenses ofan image forming optical system 222 of the single-eye image capturesection 220 in the optical axis direction.

Further, an illumination section 225 of the single-eye image capturesection 220 includes a narrow-angle illumination section 225 a having anarrow light distribution angle and a wide-angle illumination section225 b having a wide light distribution angle, and selectively uses oneof the narrow-angle illumination section 225 a and the wide-angleillumination section 225 b according to an image capture angle of thesingle-eye image capture section 220. More specifically, in a case wherethe image capture angle of the single-eye image capture section 220 is anarrow angle smaller than a predetermined angle, the narrow-angleillumination section 225 a is used for illumination for image capture.On the other hand, in a case where the image capture angle of thesingle-eye image capture section 220 is a wide angle not smaller thanthe predetermined angle, the wide-angle illumination section 225 b isused for illumination for image capture.

As described above, the narrow-angle illumination section 225 a or thewide-angle illumination section 225 b, which are different in lightdistribution angle, is selectively used according to the image captureangle of the single-eye image capture section 220, whereby it ispossible to efficiently illuminate a subject an image of which is beingcaptured using the single-eye image capture section 220. As a result, itis possible to improve the image quality of a detailed image 202. Thefollowing description is given of this control.

In general, in a case where image capture is performed using an imagecapture apparatus that is capable of changing the image capture angle,as a distance from the image capture apparatus to a subject an image ofwhich is captured is larger, it is necessary to capture an image of thesubject in an enlarged state, and hence the image capture angle isnarrowed. In other words, as the image capture angle is narrower, it isnecessary to illuminate the subject which is farther from the imagecapture apparatus. On the other hand, assuming that the amount of lightflux of illumination is constant, it is possible to make the light flux(luminous intensity) per unit angle larger by making the lightdistribution angle narrower.

Therefore, in a case where the image capture angle of the single-eyeimage capture section 220 is narrow, it is preferable to increase theluminous intensity by using the narrow-angle illumination section 225 ahaving the narrow light distribution angle. On the other hand, in a casewhere the image capture angle of the single-eye image capture section220 is wide, it is preferable to enlarge the irradiation range by usingthe wide-angle illumination section 225 b having the wide lightdistribution angle. This makes it possible to efficiently illuminate asubject an image of which is desired to be captured.

In the image capture apparatus 200, the exposure levels of a pluralityof image capture sections 211 a to 211 d forming a multi-eye imagecapture section 210 are controlled based on the image capture angle ofthe single-eye image capture section 220. More specifically, as theimage capture angle of the single-eye image capture section 220 isnarrower, the difference between the exposure level of one of the imagecapture sections 211 a to 211 d, which has an image capture range atleast partially overlapping with the image capture range of thesingle-eye image capture section 220, and the exposure level of anotherof the same, which has an image capture range not overlapping with theimage capture range of the single-eye image capture section 220, is madelarger.

With this configuration, it is possible to reduce luminance unevennessof a wide-angle image 201 as well, which is caused by a change in theillumination intensity distribution occurring when the image captureangle of the single-eye image capture section 220 is changed, and hence,it is more preferable.

The following description is given, with reference to FIGS. 5A to 5C and6A to 6C, of exposure level control for the multi-eye image capturesection 210 in a case where the image capture range of the single-eyeimage capture section 220 overlaps only with the image capture range ofone image capture section 211 a of the multi-eye image capture section210 and does not overlap with the image capture ranges of the otherimage capture sections 211 b to 211 d.

Here, FIG. 5A and FIG. 6A, each showing the image capture apparatus 200,are different in the image capture angle of the single-eye image capturesection 220, i.e. the image capture angle of the single-eye imagecapture section 220 is wider in a case of exposure level controldescribed with reference to FIGS. 6A to 6C than in a case of exposurelevel control described with reference to FIGS. 5A to 5C.

As described above, in the image capture apparatus 200 according to thesecond embodiment, as the image capture angle of the single-eye imagecapture section 220 is narrower, the light distribution angle ofillumination from the illumination section 225 is narrower. For thisreason, as shown in FIGS. 5B and 6B, as the image capture angle of thesingle-eye image capture section 220 is narrower, the peak value of theillumination intensity from the illumination section 225 is larger.Therefore, as shown in FIGS. 5C and 6C, as the image capture angle ofthe single-eye image capture section 220 is narrower, the difference inthe exposure level between the image capture section 211 a and the imagecapture sections 211 b to 211 d is made larger. This makes it possibleto reduce luminance unevenness of the wide-angle image 201 generated bysynthesis.

Next, a description will be given of a third embodiment. Componentelements of the present embodiment are denoted by reference numerals of300s. Further, the same component elements as those of the firstembodiment are denoted by reference numerals which are changed from 100sto 300s, and redundant description is omitted. Further, a functionalblock diagram of an image capture apparatus 300 according to the thirdembodiment, which corresponds to FIGS. 1C and 1 s mainly different onlyin the reference numerals from that shown in FIG. 1C, is omitted, butthe description is given using the changed reference numerals. This isalso the case with the other embodiments described hereinafter.

The image capture apparatus 300 according to the third embodimentdiffers from the image capture apparatus 100 according to the firstembodiment in that image capture sections 311 a to 311 d of a multi-eyeimage capture section 310 include photometry sections 315 a to 315 d,respectively, each of which acquires a photometric value from an imageobtained through image capture. The photometry sections 315 a to 315 dacquire photometric values which are average signal levels of imagescaptured by the image capture sections 311 a to 311 d of the multi-eyeimage capture section 310, from pixel signals read from solid-stateimage capture devices 313 a to 313 d, respectively. In doing this, acontroller 330 may set a range from which each of the photometrysections 315 a to 315 d calculates the photometric value (hereinafterreferred to as an evaluation frame) only to part of the image, and mayacquire a photometric value by performing weighted-averaging dependingon an area of the image.

Then, the exposure levels of the image capture sections 311 a to 311 dare controlled based not only on the image capture angle direction of asingle-eye image capture section 320, but also on the photometric valuesacquired by the photometry sections 315 a to 315 d, respectively. Withthis configuration, it is possible to further improve the quality of awide-angle image 301, and hence it is preferable.

The following description is given, with reference to FIGS. 7A to 7C, ofexposure level control for the multi-eye image capture section 310 in acase where the image capture range of the single-eye image capturesection 320 overlaps only with the image capture range of one imagecapture section 311 a of the multi-eye image capture section 310 anddoes not overlap with the image capture ranges of the other imagecapture sections 311 b to 311 d.

As described above, the peak of the intensity of illumination from anillumination section 325 is included in the image capture range of theimage capture section 311 a, which overlaps with the image capture rangeof the single-eye image capture section 320. However, as shown in FIG.7B, the illumination intensity of the image capture range of each of theimage capture sections 311 a to 311 d also varies with distribution ofenvironment light other than illumination light from the illuminationsection 325.

In other words, although the difference between the illuminationintensity in the image capture range of the image capture section 311 aand the illumination intensities in the image capture ranges of theimage capture section 311 b to 311 d is mainly determined byillumination light from the illumination section 325, the differencealso depends on the distribution of environment light, to be exact.Therefore, in the image capture apparatus 300 according to the thirdembodiment, the photometric values of the image capture sections 311 ato 311 d are acquired, and the difference in exposure level between theimage capture section 311 a and the image capture sections 311 b to 311d is adjusted to further reduce luminance unevenness of the wide-angleimage 301.

Note that the image capture apparatus 300 controls the exposure levelusing both of the information on the image capture direction of thesingle-eye image capture section 320 and the information on thephotometric values acquired by the photometry sections 315 a to 315 d,respectively. This makes it easier to adjust the exposure level than thecontrol of the exposure level only using the photometric values. Thefollowing description is given of the exposure level control.

FIG. 8 is a flowchart of a process for setting the exposure levels ofthe multi-eye image capture section 310. The present process isperformed by the controller 330 of the image capture apparatus 300, andthe exposure levels of the image capture sections 311 a to 311 d are setaccording to the image capture direction of the single-eye image capturesection 320.

More specifically, first, in a step S31, a user instructs the imagecapture apparatus 300 to change the image capture direction of thesingle-eye image capture section 320 from the client apparatus.

This instruction for changing the image capture direction is transmittedto the image capture apparatus 300 via the network, and the controller330 controls a drive mechanism 324 to change the image capture directionof the single-eye image capture section 320 (step S32).

The exposure levels of the image capture sections 311 a to 311 d of themulti-eye image capture section 310 are temporarily determined so as tooffset luminance differences caused by the illumination intensity oflight emitted from the illumination section 325 in the changed imagecapture direction of the single-eye image capture section 320 (stepS33). That is, the exposure levels are temporarily determined such thatthe exposure level of any of image capture sections 111 a to 111 d ofthe multi-eye image capture section 310, which has an image capturerange at least partially overlapping with the image capture range of thesingle-eye image capture section 320, is lower than the exposurelevel(s) of image capture section(s) each having an image capture rangenot overlapping with the image capture range of the single-eye imagecapture section 320.

After that, image capture is performed by the image capture sections 311a to 311 d at the exposure levels determined in the step S33,respectively, and photometric values are acquired by the photometrysections 315 a to 315 d from images acquired from the image capturesections 311 a to 311 d, respectively (step S34).

Then, in a step S35, the exposure levels of the image capture sections311 a to 311 d of the multi-eye image capture section 310 are adjustedusing the photometric values acquired by the photometry sections 315 ato 315 d in the step S34. Then, image capture is performed again by theimage capture sections 311 a to 311 d of the multi-eye image capturesection 310, and the wide-angle image 301 is generated based on theimages obtained through image capture.

The exposure levels may be adjusted, as conventionally performed, byomitting the step S33, i.e. without temporarily determining the exposurelevels of the image capture sections 311 a to 311 d of the multi-eyeimage capture section 310, and based on the photometric values acquiredfrom the images obtained through image capture performed by the imagecapture sections 311 a to 311 d of the multi-eye image capture section310 in the step S34. In this case, however, a plurality of frames areneeded or a large luminance difference is generated between the frames,before the exposure level becomes stable at the optimum exposure level.

In contrast, by temporarily determining the exposure levels of the imagecapture sections 311 a to 311 d based on the information on the imagecapture direction of the single-eye image capture section 320 in thestep S33, it is made easier to adjust the exposure levels in the stepS35. As a result, it is possible to reduce time taken to perform imagecapture at the optimum exposure levels, and hence the process shown inFIG. 8 is preferable.

As described above, according to the present embodiment, it is possibleto reduce luminance unevenness of the wide-angle image 301 moreeffectively than in a case where the exposure level is adjusted onlybased on the image capture direction of the single-eye image capturesection 320, and further, it is possible to more easily adjust theexposure level than in a case where the exposure level is adjusted usingonly the photometric values of the image capture sections 311 a to 311d.

Note that the controller 330 may set an evaluation frame within whicheach associated one of the photometry sections 315 a to 315 d acquires aphotometric value, based on the image capture direction of thesingle-eye image capture section 320. More specifically, for one(s) ofthe image capture sections 311 a to 311 d of the multi-eye image capturesection 310, each of which has an image capture range at least partiallyoverlapping with the image capture range of the single-eye image capturesection 320, it is preferable to set a central portion of the image asthe evaluation frame. This makes it possible to more positively graspthe peak of illumination intensity caused by the illumination section325. On the other hand, for ones of the image capture sections 311 a to311 d of the multi-eye image capture section 310, each of which has animage capture range not overlapping with the image capture range of thesingle-eye image capture section 320, it is preferable to set the wholeimage as the evaluation frame. This makes it possible to positivelygrasp an influence of environment light on the photometric value. Thatis, it is preferable that the controller 330 sets a narrower areaincluding the central portion of the acquired image as the evaluationframe for one of the image capture sections 311 a to 311 d of themulti-eye image capture section 310, which has an image capture rangecloser to the image capture direction of the single-eye image capturesection 320.

Next, a description will be given of a fourth embodiment. Componentelements of the present embodiment are denoted by reference numerals of400s. Further, the same component elements as those of the firstembodiment are denoted by reference numerals which are changed from 100sto 400s, and redundant description is omitted.

An image capture apparatus 400 according to the fourth embodimentdiffers from the image capture apparatus 100 according to the firstembodiment in component elements of image capture sections 411 a to 411d of a multi-eye image capture section 410. More specifically, the imagecapture sections 411 a to 411 d include focus control mechanisms 415 ato 415 d, respectively, each of which is capable of controlling a focallength. It is only required that the focus control mechanisms 415 a to415 d are each configured to include a motor and a gear and change thefocal length by moving the position of a focus lens of an associated oneof image forming optical systems 412 a to 412 d in the optical axisdirection. Further, a single-eye image capture section 420 includes aphotometry section 426 (environment light-measuring section) whichmeasures brightness of environment light as a photometric value, and animage capture mode is set to a day mode when the brightness measured bythe photometry section 426 is not lower than a predetermined value, andset to a night mode when the measured brightness is lower than thepredetermined value.

The image capture apparatus 400 controls the focal lengths of the imagecapture sections 411 a to 411 d of the multi-eye image capture section410 based on the image capture direction of the single-eye image capturesection 420. More specifically, the focal length of an image capturesection of the image capture sections 411 a to 411 d of the multi-eyeimage capture section 410, which has an image capture range at leastpartially overlapping with the image capture range of the single-eyeimage capture section 420, is controlled to a different value from thefocal length of an image capture section having an image capture rangenot overlapping with the image capture range of the single-eye imagecapture section 420. With this configuration, it is possible to furtherimprove the image quality of a wide-angle image 401. The followingdescription will be given of this control.

Here, let us assume a case where the image capture apparatus 400 is usedas a surveillance monitor provided at an entrance of a store or aparking lot. In this case, it is preferable to continuously performimage capture while focusing on a specified image capture area (theentrance in this case). Further, in a case where the image captureapparatus 400 is used e.g. for monitoring an assembly process in afactory, or used as an on-vehicle camera for detecting obstacles, it isalso preferable to continuously perform image capture while focusing ona specified image capture area.

However, in general, the image forming optical system has chromaticaberration, and hence the focal length is different depending on awavelength of light entering the image forming optical system.Particularly, as the wavelength difference is larger, the difference infocal length is larger. As a result, the following problem is caused:

For example, let us assume a case where after the focal lengths are setby the focus control mechanisms 415 a to 415 d so as to focus on asubject in daytime during which visible light mainly enters the imageforming optical systems 412 a to 412 d, near-infrared light isirradiated using an illumination section 425 during nighttime. Then, thefocal length in one of the image capture ranges of the image capturesections 411 a to 411 d, which is irradiated by the illumination section425, is shifted due to chromatic aberration between visible light andnear-infrared light, resulting in a state in which the subject is out offocus. This problem is marked in nighttime in which the near-infraredlight irradiated by the illumination section 425 mainly enters the imageforming optical systems 412 a to 415 d.

To solve this problem, in the present embodiment, the position of thefocus lens of any of the image capture sections 411 a to 411 d of themulti-eye image capture section 410, which has an image capture range atleast partially overlapping with the image capture range of thesingle-eye image capture section 420, is set again at nighttime. Bydoing this, the plurality of image capture sections 411 a to 411 d canperform image capture in a state in which the same subject is in focus.Further, this enables the image capture sections 411 a to 411 d of themulti-eye image capture section 410 to perform image capture in thestate in which the same subject is in focus regardless of daytime ornighttime, and hence is preferable.

To fix the focal length between the image capture sections 411 a to 411d of the multi-eye image capture section 410 irrespective ofillumination light, it is only required to employ the following method:

First, a controller 430 acquires information on a table shown in FIG. 9in advance, which shows a relationship between the position of the focuslens and the focal length of the image forming optical systems 412 a to412 d, for each wavelength of transmitted light.

Next, in a case where the brightness not lower than the predeterminedvalue is measured by the photometry section 426, i.e. in a case where itis determined that it is daytime, the controller 430 adjusts theposition of the focus lens to a position where the subject is in focusbased on various focusing processing, including contrast AF or phasedifference AF. For example, the position of the focus lens is adjustedto PVI_1, which is a focus lens position at time when visible lightenters, indicated in the table shown in FIG. 9.

Then, in a case where the brightness lower than the predetermined valueis measured by the photometry section 426, i.e. in a case where it isdetermined that it is nighttime, the controller 430 starts to use theillumination section 425. After starting to use the illumination section425, the controller 430 judges that in any of the image capture sections411 a to 411 d of the multi-eye image capture section 410, which has animage capture range at least partially overlapping with the imagecapture range of the single-eye image capture section 420, thewavelength of light transmitted through the image forming optical systemthereof has changed.

The position of the focus lens of the image capture section determinedas described above is adjusted to a focus lens position at time whichinfrared light enters, which is associated with the focal length set asabove, based on the table shown in FIG. 9 (lens position adjustmentunit). For example, in a case where the position of the focus lens indaytime is set to PVI_1 as in the example described above, the positionof the focus lens is changed from PVI_1 to PIR_1 for the image capturesection determined as above.

Next, a description will be given of a fifth embodiment. Componentelements of the present embodiment are denoted by reference numerals500s. Further, the same component elements as those of the firstembodiment are denoted by reference numerals which are changed from 100sto 500s, and redundant description is omitted.

An image capture apparatus 500 according to the fifth embodiment iscapable of switching the image capture mode between a day mode in whichan image is acquired only with visible light, and a night mode in whichan image is acquired with both of visible light and near-infrared light.

More specifically, the image capture mode is set to the day mode in acase where the brightness measured by a photometry section 526 is notlower than the predetermined value, and is set to the night mode in acase where the measured brightness is lower than the predeterminedvalue. Further, a plurality of image capture sections 511 a to 511 d ofa multi-eye image capture section 510 and an image capture section 521of a single-eye image capture section 520 each include an infrared cutfilter which selectively transmits visible light and selectively absorbsnear-infrared light, and an insertion/removal mechanism for insertingand removing the infrared cut filter. Here, the visible light refers tolight having a wavelength from 380 nm to 750 nm, and the near-infraredlight refers to light having a wavelength from 750 nm to 1100 nm.Further, the wavelength of illumination light irradiated from anillumination section 525 of the single-eye image capture section 520corresponds to near-infrared light.

The image capture apparatus 500 has the day mode in which the infraredcut filters are inserted into the multi-eye image capture section 510and the single-eye image capture section 520, respectively, and thenight mode in which the infrared cut filters are removed from both ofthe multi-eye image capture section 510 and the single-eye image capturesection 520. When the image capture apparatus 500 is in the night mode,image capture is performed using the illumination section 525 of thesingle-eye image capture section 520.

In the night mode, the infrared cut filter in the single-eye imagecapture section 520 is removed and the illumination section 525 in thesingle-eye image capture section 520 is used. In this case, the exposurelevels of the image capture sections 511 a to 511 d of the multi-eyeimage capture section 510 are controlled based on the image capturedirection of the single-eye image capture section 520. With thisconfiguration, it is possible to reduce luminance unevenness of awide-angle image 501. On the other hand, the illumination section 525 isnot used in the day mode and hence it is only required that a fixedexposure level is set irrespective of the image capture direction of thesingle-eye image capture section 520.

Note that the image capture apparatus 500 may be configured such that inaddition to the day mode and the night mode, there is provided a hybridmode in which the infrared cut filter of one of the multi-eye imagecapture section 510 and the single-eye image capture section 520 isremoved, and the infrared cut filter of the other is inserted.

For example, in a case where the sensitivity of a solid-state imagecapture device 523 of the single-eye image capture section 520 is lowerthan those of solid-state image capture devices 513 a to 513 d of themulti-eye image capture section 510, it is preferable to set the imagecapture mode to a mode in which the infrared cut filters of themulti-eye image capture section 510 are inserted, and the infrared cutfilter of the single-eye image capture section 520 is removed. At thistime, it is preferable to improve the SN ratio of a detailed image 502acquired by the single-eye image capture section 520 by using theillumination section 525 of the single-eye image capture section 520.However, since the infrared cut filters are inserted into the multi-eyeimage capture section 510, near-infrared light irradiated by theillumination section 525 does not enter the solid-state image capturedevices 513 a to 513 d of the multi-eye image capture section 510.Therefore, it is only required that a fixed exposure level is set forthe image capture sections 511 a to 511 d of the multi-eye image capturesection 510 irrespective of the image capture direction of thesingle-eye image capture section 520.

In a case where the sensitivities of the solid-state image capturedevices 513 a to 513 d of the multi-eye image capture section 510 arelower than that of the solid-state image capture devices 523 of thesingle-eye image capture section 520, it is preferable to set the imagecapture mode to a mode in which the infrared cut filters of themulti-eye image capture section 510 are removed, and the infrared cutfilter of the single-eye image capture section 520 is inserted. This isbecause the multi-eye image capture section 510 cannot acquire an imageof sufficient quality only with visible light even at an illuminationintensity which enables the single-eye image capture section 520 toacquire an image of sufficient quality only with the visible light.

At this time, it is more preferable to perform image capture using theillumination section 525 of the single-eye image capture section 520because the SN ratio of the wide-angle image 501 acquired by themulti-eye image capture section 510 is improved. Further, by controllingthe exposure levels of the image capture sections 511 a to 511 d of themulti-eye image capture section 510 based on the image capture directionof the single-eye image capture section 520, it is possible to reduceluminance unevenness caused by illumination distribution.

FIG. 10 shows whether or not to perform the above-described exposurelevel control based on the image capture direction of the single-eyeimage capture section 520 in the case where the mechanism for insertingand removing the infrared cut filter is included in each of themulti-eye image capture section 510 and the single-eye image capturesection 520. That is, whether or not to perform the exposure levelcontrol in the image capture apparatus 500 is determined based onwhether the infrared cut filter of each of the multi-eye image capturesection 510 and the single-eye image capture section 520 is inserted orremoved, whether or not the illumination section 525 is used, and theimage capture direction of the single-eye image capture section 520, ineach of the above-described modes. More specifically, in a case whereimage capture is performed using the illumination section 525 in a statein which the infrared cut filters of the multi-eye image capture section510 have been removed by the insertion/removal mechanism, the exposurelevel control is performed. By thus switching the exposure level controlmethod according to the image capture mode, it is possible to reduceluminance unevenness of the wide-angle image 501 irrespective of theimage capture mode.

Further, a solid-state image capture device having pixels for visiblelight and pixels for near-infrared light (hereinafter referred to as theRGBIR sensor) may be used as one or both of each of the solid-stateimage capture devices 513 a to 513 d of the multi-eye image capturesection 510 and the solid-state image capture device 523 of thesingle-eye image capture section 520. More specifically, a solid-stateimage capture device may be used in which on-chip color filters of someof pixels in the RGB Bayer array are replaced by color filters capableof transmitting only near-infrared light. On the other hand, asolid-state image capture device having only pixels for visible light inthe RGB Bayer array is referred to as the RGB sensor.

Further, in a case where the multi-eye image capture section 510 has RGBsensors as the solid-state image capture devices 513 a to 513 d, themulti-eye image capture section 510 further includes photometry sections515 a to 515 d which measure brightness of the image capture ranges ofthe image capture sections 511 a to 511 d, respectively.Insertion/removal of the infrared cut filters into/from the multi-eyeimage capture section 510 is determined according to the brightnessvalues measured by the photometry sections 515 a to 515 d.

On the other hand, in a case where the single-eye image capture section520 has an RGB sensor as the solid-state image capture device 523,insertion/removal of the infrared cut filter into/from the single-eyeimage capture section 520 is determined according to the brightnessmeasured by the photometry section 526.

FIGS. 11A to 11C show whether or not to perform exposure level controlfor the image capture sections 511 a to 511 d of the multi-eye imagecapture section 510 based on the image capture direction of thesingle-eye image capture section 520 in a case where one or both of themulti-eye image capture section 510 and the single-eye image capturesection 520 has/have (an) RGBIR sensor(s). By thus switching whether ornot to perform the exposure level control according to the image capturemode, it is possible to reduce luminance unevenness of the wide-angleimage 501 irrespective of the image capture mode.

Note that if the infrared cut filter is inserted into an image capturesection having the RGBIR sensor, infrared light is prevented fromentering the pixels for near-infrared light. For this reason, noinfrared cut filter is used in one(s) of the multi-eye image capturesection 510 and the single-eye image capture section 520, in which theRGBIR sensor(s) is/are used. That is, in a case shown in FIG. 11A, wherethe RGBIR sensors are used only in the multi-eye image capture section510, no infrared cut filters are used in the multi-eye image capturesection 510. Further, in a case shown in FIG. 11B, where the RGBIRsensor is used only in the single-eye image capture section 520, noinfrared cut filter is used in the single-eye image capture section 520.Similarly, in a case shown in FIG. 11C, where the RGBIR sensors are usedin both of the multi-eye image capture section 510 and the single-eyeimage capture section 520, no infrared cut filter is used in either ofthe multi-eye image capture section 510 and the single-eye image capturesection 520.

In a case where the multi-eye image capture section 510 has the RGBIRsensors and the single-eye image capture section 520 has the RGB sensor,the exposure level control is performed as indicated by the table shownin FIG. 11A.

A first row of settings in the table shown in FIG. 11A indicates thecontrol in a case where the brightness measured by the photometrysection 526 is not lower than a first predetermined value (the imagecapture range of the single-eye image capture section 520 is bright) andthe brightness values measured by the photometry sections 515 a to 515 dare not lower than a second predetermined value (the image capture rangeof the multi-eye image capture section 510 is bright). In this case, theinfrared cut filter is inserted into the single-eye image capturesection 520, and the illumination section 525 is not used.

A second row of settings in the table shown in FIG. 11A indicates thecontrol in a case where the brightness measured by the photometrysection 526 is not lower than the first predetermined value, but thebrightness values measured by the photometry sections 515 a to 515 d arelower than the second predetermined value (the image capture range ofthe multi-eye image capture section 510 is dark). In this case, theinfrared cut filter is inserted into the single-eye image capturesection 520, but the illumination section 525 is used to brighten theimage capture range of the multi-eye image capture section 510.

A third row of settings in the table shown in FIG. 11A indicates thecontrol in a case where the brightness measured by the photometrysection 526 is lower than the first predetermined value and thebrightness values measured by the photometry sections 515 a to 515 d arealso lower than the second predetermined value. In this case, theinfrared cut filter is removed from the single-eye image capture section520 and the illumination section 525 is used to brighten the imagecapture range of the single-eye image capture section 520.

In the case of FIG. 11A, the control based on the second and third rowsof settings is performed such that the exposure levels of the imagecapture sections 511 a to 511 d of the multi-eye image capture section510 are adjusted to eliminate an influence of the use of theillumination section 525.

Further, in a case where the multi-eye image capture section 510 has theRGB sensors and the single-eye image capture section 520 has the RGBIRsensor, the exposure level control indicated by the table shown in FIG.11B is performed.

A first row of settings in the table shown in FIG. 11B indicates thecontrol in a case where the brightness measured by the photometrysection 526 is not lower than the first predetermined value (the imagecapture range of the single-eye image capture section 520 is bright) andthe brightness values measured by the photometry sections 515 a to 515 dare not lower than the second predetermined value (the image capturerange of the multi-eye image capture section 510 is bright). In thiscase, the infrared cut filters are inserted into the multi-eye imagecapture section 510 and the illumination section 525 is not used.

A second row of settings in the table shown in FIG. 11B indicates thecontrol in a case where the brightness measured by the photometrysection 526 is lower than the first predetermined value (the imagecapture range of the single-eye image capture section 520 is dark) butthe brightness values measured by the photometry sections 515 a to 515 dare not lower than the second predetermined value (the image capturerange of the multi-eye image capture section 510 is bright). In thiscase, the infrared cut filters are inserted into the multi-eye imagecapture section 510 and the illumination section 525 is not used.

A third row of settings in the table shown in FIG. 11B indicates thecontrol in a case where the brightness measured by the photometrysection 526 is not lower than the first predetermined value (the imagecapture range of the single-eye image capture section 520 is bright) andthe brightness values measured by the photometry sections 515 a to 515 dare lower than the second predetermined value (the image capture rangeof the multi-eye image capture section 510 is dark). In this case, theinfrared cut filter is removed from the multi-eye image capture section510 and the illumination section 525 is not used.

A fourth row of settings in the table shown in FIG. 11B indicates thecontrol in a case where the brightness measured by the photometrysection 526 is lower than the first predetermined value (the imagecapture range of the single-eye image capture section 520 is dark) andthe brightness values measured by the photometry sections 515 a to 515 dare lower than the second predetermined value (the image capture rangeof the multi-eye image capture section 510 is dark). In this case, theinfrared cut filters are removed from the multi-eye image capturesection 510 and the illumination section 525 is used.

Note that even when the illumination section 525 is used, near-infraredlight irradiated by the illumination section 525 does not enter thesolid-state image capture devices 513 a to 513 d of the multi-eye imagecapture section 510 when the infrared cut filters are inserted into themulti-eye image capture section 510. Therefore, the exposure leveladjustment is performed only in a state in which the illuminationsection 525 is used and also the infrared cut filters are removed fromthe multi-eye image capture section 510 (the case indicated by thefourth row of the settings in the table shown in FIG. 11B).

Further, in a case where both of the multi-eye image capture section 510and the single-eye image capture section 520 have the RGBIR sensors, noinfrared cut filter is used in either the multi-eye image capturesection 510 or the single-eye image capture section 520. Therefore, inthis case, the exposure level control is performed only based on acondition of use/non-use of the illumination section 525, as indicatedby the table shown in FIG. 11C.

Note that in a case where the RGB sensors are used in both of themulti-eye image capture section 510 and the single-eye image capturesection 520, whether or not to perform the exposure level control may beswitched as shown in FIG. 10.

OTHER EMBODIMENTS

Embodiment(s) of the present invention can also be realized by acomputer of a system or apparatus that reads out and executes computerexecutable instructions (e.g., one or more programs) recorded on astorage medium (which may also be referred to more fully as a‘non-transitory computer-readable storage medium’) to perform thefunctions of one or more of the above-described embodiment(s) and/orthat includes one or more circuits (e.g., application specificintegrated circuit (ASIC)) for performing the functions of one or moreof the above-described embodiment(s), and by a method performed by thecomputer of the system or apparatus by, for example, reading out andexecuting the computer executable instructions from the storage mediumto perform the functions of one or more of the above-describedembodiment(s) and/or controlling the one or more circuits to perform thefunctions of one or more of the above-described embodiment(s). Thecomputer may comprise one or more processors (e.g., central processingunit (CPU), micro processing unit (MPU)) and may include a network ofseparate computers or separate processors to read out and execute thecomputer executable instructions. The computer executable instructionsmay be provided to the computer, for example, from a network or thestorage medium. The storage medium may include, for example, one or moreof a hard disk, a random-access memory (RAM), a read only memory (ROM),a storage of distributed computing systems, an optical disk (such as acompact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™),a flash memory device, a memory card, and the like.

While the present invention has been described with reference toexemplary embodiments, it is to be understood that the invention is notlimited to the disclosed exemplary embodiments. The scope of thefollowing claims is to be accorded the broadest interpretation so as toencompass all such modifications and equivalent structures andfunctions.

This application claims the benefit of Japanese Patent Application No.2018-161685 filed Aug. 30, 2018, which is hereby incorporated byreference herein in its entirety.

What is claimed is:
 1. An image capture apparatus comprising: amulti-eye image capture portion comprising a plurality of image capturesections that capture images in image capture ranges partiallyoverlapping with each other so as to generate a wide-angle image; asingle-eye image capture portion that is capable of capturing an imagein part of the image capture ranges of the multi-eye image captureportion and is capable of changing an image capture direction; anillumination section that has a peak of illumination intensity within afirst image capture range of the single-eye image capture portion; atleast one memory that stores a set of instructions; and at least oneprocessor that executes the instructions, the instructions, whenexecuted, causing the image capture apparatus to perform operationscomprising: controlling, when performing image capture using theillumination section, a first exposure level of a first image capturesection of the plurality of image capture sections of the multi-eyeimage capture portion such that the first exposure level of the firstimage capture section becomes lower than a second exposure level of asecond image capture section of the plurality of image capture sections,wherein an image capture range of the first image capture section of theplurality of image capture sections overlaps with the first imagecapture range of the single-eye image capture portion, and wherein animage capture range of the second image capture section of the pluralityof image capture sections does not overlap with the first image capturerange of the single-eye image capture portion.
 2. The image captureapparatus according to claim 1, wherein the instructions further includean instruction for controlling an exposure level of an image capturesection of the plurality of image capture sections of the multi-eyeimage capture portion, which captures an image in an image capture rangecloser to the image capture direction of the single-eye image captureportion, to be lower.
 3. The image capture apparatus according to claim1, wherein the instructions further include an instruction for setting,in a case where spread of illumination intensity distribution by theillumination section is narrower than the first image capture range ofthe single-eye image capture portion and the second image capturesection exists in plurality, the second exposure level of the secondimage capture sections to a common value.
 4. The image capture apparatusaccording to claim 1, wherein the instructions further include aninstruction for performing, in a case where the peak of the illuminationintensity of the illumination section coincides with the image capturedirection of the single-eye image capture portion, shading correctionfor making higher a pixel signal level of an image capture section ofthe plurality of image capture sections of the multi-eye image captureportion, as the image capture section is farther from the image capturedirection of the single-eye image capture portion.
 5. The image captureapparatus according to claim 1, wherein the plurality of image capturesections forming the multi-eye image capture portion each include anillumination section having a peak of illumination intensity within animage capture range thereof.
 6. The image capture apparatus according toclaim 1, wherein the instructions further include an instruction forcontrolling a frame rate of the second image capture section such thatthe frame rate becomes lower than a frame rate of the first imagecapture section.
 7. The image capture apparatus according to claim 1,wherein the illumination section includes a narrow-angle illuminationsection and a wide-angle illumination section which is wider in lightdistribution angle than the narrow-angle illumination section, and usesthe narrow-angle illumination section for illumination during imagecapture in a case where an image capture angle of the single-eye imagecapture portion is smaller than a predetermined angle, and thewide-angle illumination section for illumination during image capture ina case where the image capture angle of the single-eye image captureportion is not smaller than the predetermined angle.
 8. The imagecapture apparatus according to claim 1, further comprising a zoomcontrol mechanism that is capable of changing the image capture angle ofthe single-eye image capture portion, wherein the instructions furtherinclude an instruction for making a difference larger between the firstexposure level of the first image capture section and the secondexposure level of the second image capture section as the image captureangle of the single-eye image capture portion is narrower.
 9. The imagecapture apparatus according to claim 1, wherein the instructions furtherinclude instructions for: temporarily determining the exposure level ofthe first image capture section such that the exposure level becomes avalue lower than the exposure level of the second image capture sectionin a case where the image capture direction of the single-eye imagecapture portion is changed, causing the plurality of image capturesections to perform image capture at the temporarily determined exposurelevels to acquire images from the plurality of image capture sections,respectively, acquiring a photometric value from an image acquiredthrough image capture by each of the plurality of image capture sectionsof the multi-eye image capture portion, and adjusting the exposurelevels of the plurality of image capture sections using the acquiredphotometric values, respectively.
 10. The image capture apparatusaccording to claim 1, wherein the instructions further includeinstructions for: setting a range for calculating the photometric value,in part of the acquired image, as an evaluation frame, and setting anarrower area including a central portion of the acquired image as theevaluation frame for an image capture section of the plurality of imagecapture sections of the multi-eye image capture portion, which has animage capture range closer to the image capture direction of thesingle-eye image capture portion.
 11. The image capture apparatusaccording to claim 1, wherein a wavelength of illumination of theillumination section corresponds to near-infrared light, wherein themulti-eye image capture portion and the single-eye image capture portioneach further include an infrared cut filter which selectively transmitsvisible light and selectively absorbs near-infrared light, and aninsertion/removal mechanism for inserting and removing the infrared cutfilter, and wherein the instructions further include instructions for:performing exposure level control for the plurality of image capturesections of the multi-eye image capture portion in a case where imagecapture is performed using the illumination section in a state in whichthe infrared cut filters of the multi-eye image capture portion areremoved by the insertion/removal mechanism.
 12. The image captureapparatus according to claim 11, wherein at least one of the multi-eyeimage capture portion and the single-eye image capture portion includesa solid-state image capture device having pixels for visible light andpixels for near-infrared light.
 13. The image capture apparatusaccording to claim 11, wherein the plurality of image capture sectionsof the multi-eye image capture portion each include a focus controlmechanism which is capable of controlling a focal length by moving aposition of a focus lens, and the single-eye image capture portionfurther includes an environment light photometry section which measuresbrightness of environment light, and wherein the instructions furtherinclude instructions for: (a) causing the focus control mechanism tomove each associated one of all focus lenses of the plurality of imagecapture sections of the multi-eye image capture portion to a first focuslens position when visible light enters, in a case where brightnessmeasured by the environment light photometry section is not lower than apredetermined value, and (b) starting to use the illumination sectionand adjusting a position of the focus lens of the first image capturesection to a second focus lens position when infrared light enters, suchthat a focal length of the focus lens corresponds to the first focuslens position at a time when visible light enters, in a case wherebrightness measured by the environment light photometry section is lowerthan the predetermined value.
 14. The image capture apparatus accordingto claim 1, wherein the instructions further include an instruction forgenerating the wide-angle image.
 15. The image capture apparatusaccording to claim 1, wherein the instructions further include aninstruction for outputting the plurality of images to an externalapparatus that generates the wide-angle image.
 16. A monitoring systemincluding an image capture apparatus and an information processingapparatus, wherein the image capture apparatus comprises: (a) amulti-eye image capture portion having a plurality of image capturesections that capture images in image capture ranges partiallyoverlapping with each other so as to generate a wide-angle image; (b) asingle-eye image capture portion that is capable of capturing an imagein part of the image capture ranges of the multi-eye image captureportion and is capable of changing an image capture direction; (c) anillumination section that has a peak of illumination intensity within afirst image capture range of the single-eye image capture portion; (d)at least one memory that stores a set of instructions; and (e) at leastone processor that executes the instructions, the instructions, whenexecuted, causing the image capture apparatus to perform operationscomprising: controlling, when performing image capture using theillumination section, a first exposure level of a first image capturesection of the plurality of image capture sections of the multi-eyeimage capture portion, such that the first exposure level of the firstimage capture section becomes lower than a second exposure level of asecond image capture section of the plurality of image capture sections,wherein an image capture range of the first image capture section of theplurality of image capture sections overlaps with the first imagecapture range of the single-eye image capture portion, and wherein animage capture range of the second image capture section of the pluralityof image capture sections does not overlap with the first image capturerange of the single-eye image capture portion, and wherein theinformation processing apparatus displays the wide-angle image and animage captured by the single-eye image capture portion, and transmits aninstruction for controlling the image capture apparatus to the imagecapture apparatus.
 17. A method of controlling an image captureapparatus including (a) a multi-eye image capture portion having aplurality of image capture sections that capture images in image captureranges partially overlapping with each other so as to generate awide-angle image, (b) a single-eye image capture portion that is capableof capturing an image in part of the image capture ranges of themulti-eye image capture portion and is capable of changing an imagecapture direction, and (c) an illumination section that has a peak ofillumination intensity within a first image capture range of thesingle-eye image capture portion, the method comprising: controlling,when performing image capture using the illumination section, a firstexposure level of a first image capture section of the plurality ofimage capture sections of the multi-eye image capture portion such thatthe first exposure level of the first image capture section becomeslower than a second exposure level of a second image capture section ofthe plurality of image capture sections, wherein an image capture rangeof the first image capture section of the plurality of image capturesections overlaps with the first image capture range of the single-eyeimage capture portion, and wherein an image capture range of the secondimage capture section of the plurality of image capture sections doesnot overlap with the first image capture range of the single-eye imagecapture portion.
 18. A non-transitory computer-readable storage mediumstoring a computer-executable program for executing a method ofcontrolling an image capture apparatus including (a) a multi-eye imagecapture portion having a plurality of image capture sections thatcapture images in image capture ranges partially overlapping with eachother so as to generate a wide-angle image, (b) a single-eye imagecapture portion that is capable of capturing an image in part of theimage capture ranges of the multi-eye image capture portion and iscapable of changing an image capture direction, and (c) an illuminationsection that has a peak of illumination intensity within a first imagecapture range of the single-eye image capture portion, wherein themethod comprises: controlling, when performing image capture using theillumination section, a first exposure level of a first image capturesection of the plurality of image capture sections of the multi-eyeimage capture portion such that the first exposure level of the firstimage capture section becomes lower than a second exposure level of asecond image capture section of the plurality of image capture sections,wherein an image capture range of the first image capture section of theplurality of image capture sections overlaps with the first imagecapture range of the single-eye image capture portion, and wherein animage capture range of the second image capture section of the pluralityof image capture sections does not overlap with the first image capturerange of the single-eye image capture portion.